Hericium

The Hericium genus, often known as Lion's Mane, consists of basidiomycete fungi that primarily function as saprotrophs but can act as facultative parasites. In an agricultural and forestry context, they are associated with the development of white heart rot, which compromises the structural integrity of various deciduous trees.

This fungus typically attacks fruit trees such as apples and pears, as well as forest species like oaks and beeches. Infection sites are almost always associated with wounds in the bark, improperly healed pruning cuts, or frost cracks, which provide the pathogen with access to the susceptible heartwood.

Symptoms include the emergence of distinctive, icicle-like fruiting bodies on the trunk or branches. Internally, the fungus degrades lignin and cellulose, resulting in a light-colored, spongy, and fibrous wood texture. As the decay progresses, the tree becomes significantly weakened, increasing the risk of breakage during storms.

The development of the disease is highly dependent on environmental conditions, particularly high humidity and poor aeration within the canopy. Spores are disseminated by air currents and rain splashes, often colonizing tissues that have already started the process of natural senescence or mechanical wounding.

Control strategies emphasize preventative care: proper pruning techniques that allow for rapid callus formation, and the application of wound dressings or fungicides to any damaged tissue. If the fungus is detected, it is essential to excise the fruiting bodies and dead wood to mitigate further decay, while maintaining tree vigor through balanced fertilization and irrigation.